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A133457 Irregular triangle read by rows: row n gives exponents in expression for n as a sum of powers of 2. +0
2
0, 1, 0, 1, 2, 0, 2, 1, 2, 0, 1, 2, 3, 0, 3, 1, 3, 0, 1, 3, 2, 3, 0, 2, 3, 1, 2, 3, 0, 1, 2, 3, 4, 0, 4, 1, 4, 0, 1, 4, 2, 4, 0, 2, 4, 1, 2, 4, 0, 1, 2, 4, 3, 4, 0, 3, 4, 1, 3, 4, 0, 1, 3, 4, 2, 3, 4, 0, 2, 3, 4, 1, 2, 3, 4, 0, 1, 2, 3, 4, 5, 0, 5, 1, 5, 0, 1, 5, 2, 5, 0, 2, 5, 1, 2, 5, 0, 1, 2, 5, 3, 5, 0, 3, 5 (list; graph; listen)
OFFSET

1,5

COMMENT

This sequence contains every increasing finite sequence. For example, the finite sequence {0,2,3,5} arises from n = 45.

Essentially A030308(n,k)*k, then entries removed where A030308(n,k)=0. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 30 2007

EXAMPLE

1 = 2^0

2 = 2^1

3 = 2^0 + 2^1

4 = 2^2

5 = 2^0 + 2^2

etc. and reading the exponents gives the rows of the triangle.

MAPLE

A133457 := proc(n) local a, bdigs, i ; a := [] ; bdigs := convert(n, base, 2) ; for i from 1 to nops(bdigs) do if op(i, bdigs) <> 0 then a := [op(a), i-1] ; fi ; od: a ; end: seq(op(A133457(n)), n=1..80) ; - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 30 2007

CROSSREFS

Cf. A067255.

Sequence in context: A127543 A068907 A033687 this_sequence A068067 A046926 A074398

Adjacent sequences: A133454 A133455 A133456 this_sequence A133458 A133459 A133460

KEYWORD

base,tabf,easy,nonn

AUTHOR

Masahiko Shin (nin-ts5406(AT)w9.dion.ne.jp), Nov 27 2007

EXTENSIONS

More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 30 2007

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Last modified December 10 00:48 EST 2009. Contains 170565 sequences.


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